1. Field of the Invention
Aspects of the present invention relate to an organic light emitting diode display device and a method for driving the same, which can easily discriminate whether or not a crack occurred in a sealing material, before abnormalities occur.
2. Description of the Related Art
Generally, organic light emitting diode display devices are emissive type displays which electrically excite fluorescent organic compounds to emit light. The organic light emitting diode display devices can be driven at a low voltage, can be reduced in thickness, and can solve problems of liquid crystal display devices related to a wide viewing angle and a rapid response speed. Therefore, studies on the organic light emitting diode display devices are being actively conducted.
Such an organic light emitting diode display device includes an organic emission layer formed on a glass substrate or a transparent insulating substrate equivalent to glass, and anodic and cathodic electrode layers respectively formed on and under the organic emission layer to apply a driving voltage to the organic emission layer.
In the organic light emitting diode display device having the above-described configuration, as positive and negative voltages are applied to the electrodes, holes injected from the electrode to which the positive voltage is applied move to the organic emission layer, and electrons are injected to the organic emission layer from the electrode to which the negative voltage is applied. Accordingly, the electrons and the holes are recombined in the organic emission layer to generate exitons. While the exitons change from the exited state to the ground state, organic matters of the organic emission layer emit light to implement a desirable image.
The configuration of a contemporary organic light emitting diode display device may be described as follows. The contemporary organic light emitting diode display device includes a stacked-structure thin film transistor and an organic light emitting diode constituted by a first electrode, an organic emission layer, and a second electrode, which are formed on a first substrate having transparency and insulating properties. The thin film transistor and the organic light emitting diode are electrically connected.
As a second substrate is joined to the first substrate having the thin film transistor and the organic light emitting diode formed thereon through a sealing material, the thin film transistor and the organic light emitting diode are sealed.
In general, the sealing material is applied along an edge of the first or second substrate, and is cured by applying heat to the sealing material in a state in which the first and second substrates are bonded to each other.
When a minute crack occurs in the sealing material, the display is not turned off immediately or an error does not occur immediately. But, the display is turned off after a predetermined time passes.
This is because air, oxygen, moisture and so on permeate into cells through the minute crack little by little to destroy the organic light emitting diode.
Therefore, it takes time to check why the display device has been out of order. Users may recognize that the display device has been suddenly out of order without any reason.